I (Scott) decided to use untreated and unpainted 1″ x 4″ boards for the top trim of the grow bed. They will rot and need to be replaced in a few years, but I wanted to minimize the chemicals that would leach into the water from paint, stain, or lacquer when it rains. We also like the way it looks…for now at least.

The pipe is sloped from the fish tank to the other end of the grow bed. Small pieces of one-by-four were used as support for the pipe.

Here is the end of the pipe that will direct water into the grow bed from the fish tank. This photo also shows the nylon material that is used to hold the pipe to the grow bed trim.

I filled the grow bed with water today to make sure there were no leaks. We should be finishing the system very soon…hopefully tomorrow or Monday. More photos coming soon.

Yesterday we also celebrated my 47th birthday. My 3-year-old son decided that he wanted me to have a tilapia birthday cake. No, it wasn’t made of tilapia; it just had a picture of our tilapia on top. The fish in the bottom, left-hand corner of the cake is Bacon. I got that piece 🙂

WOW, that is a really interesting system you put together. I’m anxious to see how it goes for you. I was just discussing hydroponics with someone the other day as one of the things i’d like to try. I also have been thinking about a small “fish farm” in the backyard. Still in the thinking stages.
Venessa

I really like the look of untreated wood, too, but as you said, it won’t last long. Luckily, once it starts graying you can paint it with homemade milk paint, which is nontoxic. Recipes are easy to find, but here’s a link to a company site that provides a few recipes for free, including a water-resistant one. http://www.realmilkpaint.com/recipe.html

Thank you Anne! An all natural paint that is non-toxic to the plants or fish is exactly what we need. I wonder if we could make the milk paint without the lime, because lime would most likely raise the pH of the water if it leached into the system when it rains.

I doubt that the amount of lime that would leech during rain would be significant. Since I’m sure you have a testing kit, I would just recommend you keep an eye on it. If it raises much, you can balance it out. But, honestly, based on the size of your system and the small surface that would be painted, the affect will likely be negligible and the system should self balance. It’s not like a build-up would occur. Try it on a small portion at first, or maybe email the milk paint site and see if they think it would leech and how much. If it leeches a ridiculously small ratio, such as a gram per 500 gallons (which is probably way more than could possibly leech at one time), then you can rest easy.